5.3 or 4.8?
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5.3 or 4.8? Pulled a motor out of a 2004 Chevy Silverado 1500. Figures for sure it was a 5.3L. Now I’m worried I got a 4.8L . Originally didn’t want to get away from the 5.7 original LT1 I had but read a lot about the 5.3 and liked the idea of boosting it. The block says both which I read is normal. It’s a iron block. Aluminum heads had 4.8L stamped inside of one of the valleys and they are flat top pistons with a cross sign stamped on them.. Haven’t pulled the oil pan yet as still cleaning things up on heads. Really bummed out and hoping the head stamp doesn’t mean anything... oh and 862 heads if anyone was wondering. Also I did search and found mixed results so wanted to post on here. Thanks!
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Given that you already mentioned boost, what does it matter if you have a 4.8L vs a 5.3L?
From a performance standpoint, they are similar enough that it's not worth getting bummed about.
I know you said you didn't want to stray too far from the 5.7L LT1, but displacement is just a number... a stock 4.8L performs just as well as a stock 5.7L LT1... 300hp is 300hp.
From a performance standpoint, they are similar enough that it's not worth getting bummed about.
I know you said you didn't want to stray too far from the 5.7L LT1, but displacement is just a number... a stock 4.8L performs just as well as a stock 5.7L LT1... 300hp is 300hp.
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Well they sound different for one reason. LT1 with some stuff done to it sounds mean as my old setup did.. 5.3 sounds pretty good too but the 4.8L I have heard that guys put exhaust on for the trucks just don’t sound as mean. The displacement thing makes a difference, sure I can build around it but just wanted a 5.3. Mechanic friend I talked to said it happens pretty often unless you have the time in the junkyard to look at the crank stamping.
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I read some years 5.3 had flat tops... Would it be crazy to bother getting a stock 5.3 rotating assembly and swapping out from a junkyard or wherever? I know someone that has one but pistons have damage from valves hitting them.
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All Gen III 5.3's with 706/862 heads have dish pistons.
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The VIN of the vehicle the engine came from will tell you displacement. If you're going turbo who gives a turkey. If you are so concerned about a few cubes or it won't sound "mean" enough (whatever that is) I agree with Michael, sell it and move on.
I understand there is no replacement for displacement but that only applies if you're trying to make maximum power as in racing. Honestly no one will know unless you tell them and the remaining people won't understand the difference or care. I would also bet a nickel in a double blind test you won't be able to tell the difference 10 for 10 on your butt dyno in the same chassis.
I understand there is no replacement for displacement but that only applies if you're trying to make maximum power as in racing. Honestly no one will know unless you tell them and the remaining people won't understand the difference or care. I would also bet a nickel in a double blind test you won't be able to tell the difference 10 for 10 on your butt dyno in the same chassis.
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I know you guys are right but have it stuck in my mind 
. Like I asked would it be worth the hassle to switch out to a 5.3 rotating assembly? Truck is 2hrs away so can’t go check it. But think it was a two door and not a crew cab...
. Like I asked would it be worth the hassle to switch out to a 5.3 rotating assembly? Truck is 2hrs away so can’t go check it. But think it was a two door and not a crew cab... "....would it be worth the hassle...." --- "I.....have it stuck in my mind." What is it you want us to help you with? If you absolutely want a 5.3 (have it stuck in my mind) - then make it a 5.3L. You don't need our help with that.
Where are you gonna get the rotating assembly?
Where are you gonna get the rotating assembly?
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Well they sound different for one reason. LT1 with some stuff done to it sounds mean as my old setup did.. 5.3 sounds pretty good too but the 4.8L I have heard that guys put exhaust on for the trucks just don’t sound as mean. The displacement thing makes a difference, sure I can build around it but just wanted a 5.3. Mechanic friend I talked to said it happens pretty often unless you have the time in the junkyard to look at the crank stamping.